Depositional Environment Of The Late Precambrian Fossil-bearing Rocks of Southeastern Newfoundland, Canada

Abstract

Thin bedded cherts and siliceous argillites of the Drook and Fresh Water Point Formations of the Conception Group were deposited above the wave base in most parts, as evident from the nature of bedding, large, scale ripple marks, penecontemporaneous deformation and calcareous nodules. The overlying Cape cove Formation of the same group is characterized by graded greywackes presumably deposited by turbidity currents. The animals that lived in the Conception sea during deposition of the Cape Cove Formation include pelagic as well as bottom dwellers. The presence of large-scale slump structures in the St. John's Formation (new group) indicate a gently sloping surface of he depositional basin. The depositional environment of the St. John's Formation had become shallower than that of the underlying Conception Group.